大鼠衰老模型的初步建立

目的　探讨D 半乳糖皮下注射法致大鼠衰老的合适剂量 ,复制可靠的大鼠衰老模型。方法　实验分为D 半乳糖 0 0 75g kg组、0 1g kg组、0 12 5g kg组、3月龄对照组、2 4月龄对照组 (n =10 )。前 3组每天给予D 半乳糖皮下注射 ,对照组皮下注射等量生理盐水 ,40d后观测脑中B型单胺氧化酶 (MAO B)活性、血清超氧化物歧化酶 (SOD)活性、血清脂质过氧化物 (LPO)含量 ,脑、心肌、肝中脂褐素含量 ,血清溶血素水平 ,胸腺指数、脾脏指数、体重增长率 ,血糖、血清胆固醇含量的变化。结果　各致衰组和 2 4月龄组的脑中MAO B活性、血清LPO含量均较 3月龄组显著增高 (P <0 0 1) ;血清SOD活性较 3月龄组降低 (P <0 0 1) ;脑、心肌、肝中脂褐素含量均较 3月龄组增高 (P <0 0 1) ;血清溶血素水平、胸腺指数、脾脏指数仅 0 12 5g kg组和 2 4月龄组较 3月龄组显著降低 (分别 :P <0 0 5 ;P <0 0 1;P <0 0 1) ;各致衰组的血糖与 3月龄组间无显著差异 ;血清胆固醇仅 0 1g kg组显著增高 (P <0 0 1) ;体重增长率较 3月龄组显著降低 (P <0 0 1)。以上变化中 0 12 5g kg组与 2 4月龄组之间无显著差异 (P >0 0 5 )。结论　D 半乳糖 0 12 5g·kg- 1 ·d- 1 皮下注射 40d可以复制出与 2 4月龄大鼠衰老程度近似的大鼠衰

Preliminary establishment of aging model in rat

Objective To investigate the suitable dosage of the aging model induced by D galactose injected subcutaneously and the reliability of this aging model. Methods Forty three month old rats were randomly divided into 4 groups ( n =10): 0.075 g/kg D galactose group, 0.1 g/kg -1 D galactose group, 0.125 g/kg D galactose group, and 3 month old control group. The D galactose groups received D galactose injected subcutaneously once per day. Ten twenty four month rats were set as another control group. The two control groups were injected subcutaneously with equivalent saline. The following indices were observed 40 days later: the activity of MAO B in the brain tissue, the activity of superoxide dismutase(SOD) and the content of the lipid peroxides(LPO) in serum, the contents of lipofuscin in brain, heart and liver, the content of hemolysin in serum, the thymus weight index, the spleen weight index, the growth rate of weight, the blood sugar and cholesterol in serum. Results Compared with those in 3 month group, the activity of MAO B in the brain tissue and the content of the LPO of each D galactose group and 24 month group increased respectively ( P <0.01); the activity of SOD of each D galactose group and 24 month group decreased ( P <0.01); the contents of lipofuscin in brain, heart and liver increased ( P <0.01); the content of hemolysin in serum, the thymus weight index and the spleen weight index of D galactose 0.125 g/kg group and 24 month group decreased ( P <0.01); no significant difference of blood sugar was found between D galactose group and 3 month group; cholesterol in serum of D galactose 0.1 g/kg group increased ( P <0.01); the growth rate of weight decreased ( P <0.01). These changes of D galactose 0.125 g/kg group were similar to those in 24 month group ( P >0.05). Conclusion The dosage of 0.125 g/kg of D galactose injected subcutaneously once per day for 40 days can reproduce the aging model of the twenty four month old rat.